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Updating existing Roof Components instead of creating new ones on update in Grasshopper


I am creating a roof in Grasshopper based on anchor points of columns in AC.
When I move one of the columns, instead of updating the existing roof, it creates a new one. 
This results in a new GUID and loosing all solid element operations / placed windows.
Is there any way to avoid this behaviour and instead just update the exisiting roof component?


Operating system used: Windows



Some more information would be helpful. Can you provide a screenshot of your GH-script?

AC16 -> AC aktuell
WIN 10 & Mac Studio Ventura

This is a minimal working example:


I have four columns in Archicad connected to GH. When I move them, the roof is recreated and not refreshed, thus it looses for example it's windows and gets a new GUID.
I'm not sure if this is the expected behavior, but it's a big problem for our workflow.

Edit: Interestingly, if I modify the geometry by moving the points in GH and not the columns in AC, the roof is not recreated but updated as expected.

So it is a workaround to just move the refernce points in GH without recreating the roof. But just one accidential recompute/F5 leads to a recreation/loosing all windows and so on.


I've experienced the same behaviour but there is a way to get around this. Add a boolean toggle to your skript. Then break the sync with set to "False", move your columns in AC and set back to "True". The roof will update then without loosing the window and the unique ID.Boolean_Toggle.png






AC16 -> AC aktuell
WIN 10 & Mac Studio Ventura
Laszlo Nagy
Community Admin
Community Admin

FYI: Yes, the Grasshopper Connection currently does not have the capability to update elements already existing in Archicad. It can only create new Archicad elements, and when any parameter changes in Grasshopper, it will delete those created elements and create new ones. This is why the GUID changes.

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